Joined: May 2002
Over on this ARN thread,
...Joy & Mike Gene are missing JP's point. As explanatory hypotheses in science, an unconstrained supernatural designer and an unconstrained natural designer (or an unconstrained designer of unspecified supernaturalness or naturalness) have the same problem: they have no empirical implications.
(I am speaking of "constraint" in terms of "explanatory constraint" here -- an omnipotent designer or super-technological designer would be all-powerful but would still be a "constrained" explanation if his actions followed a pattern motivated by a specific goals. But an unconstrained ID hypothesis is essentially what is often called "rarified design")
Note that the point is not that we have to know these things about the IDer ahead of time, the point is that we have to hypothesize something with some empirical implications so that we have some idea of what kinds of evidence would strengthen or weaken our confidence in the hypothesis.
Otherwise nothing is getting explained at all, even hypothetically.
The two major explanatory constraints that can begin to elevate design hypotheses to something above the "IDdidit" level are, I think:
1) Designer methods/capabilities
2) Designer goals
...although there may be others. Notably, for human-design hypotheses we have a lot of evidence informing both #1 and #2, even for prehistoric cases.
For SETI, the scientists involved are quite clearly hypothesizing that alien designers will be like us in certain minimal but ways, namely:
1) Designer methods/capabilities: radio
2) Designer goals: interstellar communication (with us or others)
If either of these hypotheses is wrong, then even if the universe is teeming with intelligent life, we will not discover it through SETI no matter how much money and time are put in. This is not a weakness but a strength: the status of the hypothesis can be fairly rigorously evaluated at any point. Currently it is:
Positive evidence: none
Negative evidence: a little bit (nothing found with current restricted detection limits)
As for the general likelihood of intelligent life in the universe, this can begin to be assessed if we constrain our "existence of intelligent life" hypothesis to something like "basically like human life and formed by the same processes we think created us".
If, on the other hand, our "existence of intelligent life" hypothesis is "intelligent life of unknown characteristics formed by unknown processes" then we have no basis on which to procede and the hypothesis is relegated to the shrugworthy category of "undetectable invisible pixies exist".
As for ID, I think that IDists do specify constraints #1 and/or #2 fairly regularly, it's just that they usually do it in passing (or even in a semi-hidden fashion) rather than explicitly, they tend to deny such specifications in public, and when an ID skeptic thinks they detect a specific hypothesis and raises counterevidence that weakens it, the IDist tends to deny that such a specific hypothesis was ever proposed. Such vagueness may be helpful in debates, but it stands no chance of moving the ID ball towards the goal line of science.